Fiber optic closure

ABSTRACT

A fiber optic communications arrangement includes a closure with an interior volume; the closure including at least one cable through-port in communication with the interior volume; and an expansion component attached to an exterior portion of the closure and having an interior region in communication with the closure interior volume. The expansion component includes ruggedized fiber optic adapters mounted thereto. Each of the ruggedized fiber optic adapters includes at least one connector port for receiving ruggedized fiber optic connectors.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of application Ser. 15/289,459, filedOct. 10, 2016, which is a continuation of application Ser. No.14/716,347, filed May 19, 2015, now abandoned, which is a divisional ofapplication Ser. No. 14/495,110, filed Sep. 24, 2014, now U.S. Pat. No.9,057,858, issued Jun. 16, 2015, which is a divisional of applicationSer. No. 13/397,884, filed Feb. 16, 2012, now U.S. Pat. No. 8,861,919,issued Oct. 14, 2014, which application claims the benefit ofprovisional application Ser. No. 61/468,405, filed Mar. 28, 2011 andprovisional application Serial No. 61/443,501, filed Feb. 16, 2011,which applications are incorporated herein by reference in theirentireties.

TECHNICAL FIELD

The present disclosure relates generally to components for fiber opticcommunications networks. More particularly, the present disclosurerelates to sealed closures used in fiber optic networks.

BACKGROUND

Fiber optic communications systems are becoming prevalent in partbecause service providers want to deliver high band width communicationcapabilities to customers. Fiber optic communications systems employ anetwork of fiber optic cables to transmit large volumes of data andvoice signals over relatively long distances. A typical fiber opticnetwork includes a system of trunk fiber optic cables each including arelatively large number of optical fibers. Fiber optic networks alsoinclude drop cables that interconnect to fibers of the trunk cables atvarious locations along the lengths of the trunk cables. The drop cablescan be routed from the trunk cables to subscriber locations or tointermediate structures such as drop terminals.

Drop cables are often connected to the optical fibers of trunk cablesvia splices (e.g., fusion splices). Splices are typically supportedwithin splice trays that are often protected from the environment bysealed, re-enterable closures. Such closures typically include sealedports through which the trunk cables and drop cables enter the closures.Example dome-style splice closures are disclosed in U.S. Pat. Nos.7,780,173; 5,446,823; and 5,323,480; which patents are herebyincorporated by reference in their entireties.

Drop cables can also be connected to trunk cables through the use offiber optic connectors (e.g., non-ruggedized connectors or ruggedizedconnectors). Non-ruggedized connectors are generally less robust thatruggedized connectors. Also, in contrast to non-ruggedized connectors,ruggedized connectors are typically equipped with seals. Because oftheir non-robust and unsealed structure, non-ruggedized connectors aregenerally used for inside applications or within sealed closures. Incontrast, because of their robust and sealed structure, ruggedizedconnectors can be used in outside applications where they are exposed tothe environment. The use of ruggedized fiber optic connection systemsallows pre-connectorized drop cables to be connected to fibers of atrunk cable without accessing the inside of a splice closure. Forexample, the drop cables can include ruggedized connectors that pluginto ruggedized adapters mounted on the outside wall of a spliceclosure. An example splice enclosure including ruggedized adapters isdisclosed in U.S. Pat. No. 7,013,074.

Drop cables can often be routed from a trunk cable to an intermediatestructure such as a drop terminal. Drop terminals equipped withruggedized adapters are disclosed in U.S. Pat. Nos. 7,292,763;7,120,347; and 7,266,244.

SUMMARY

Certain aspects of the present disclosure relate to devices and methodsfor upgrading/retrofitting splice closures that have already beeninstalled in the field. For example, the splice closures can beupgraded/retrofitted to include ruggedized fiber optic adaptersconfigured for receiving ruggedized fiber optic connectors mounted atthe ends of drop cables.

Another aspect of the present disclosure relates to a dome-style spliceclosure configured to accommodate the internal splicing of drop cablesand also being configured to interconnect with drop cables terminatedwith ruggedized connectors.

A further aspect of the present disclosure relates to structures andmethods for providing closures that have splicing capabilities and arealso compatible with pre-connectorized drop cables.

Still another aspect of the present disclosure relates to componenttrays/cassettes adapted for use in upgrading/retrofitting spliceclosures.

A variety of additional inventive aspects will be set forth in thedescription that follows. The inventive aspects can relate to individualfeatures and to combinations of features. It is to be understood thatboth the foregoing general description and the following detaileddescription are exemplary and explanatory only and are not restrictiveof the broad inventive concepts upon which the embodiments disclosureherein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a dome-style closure in accordance withthe principles of the present disclosure;

FIG. 2 is a perspective view of the closure of FIG. 1 with the domeremoved to expose a stack of splice trays;

FIG. 3 shows the closure of FIG. 1 with the dome removed and one of thesplice trays of the stack of splice trays pivoted downwardly;

FIG. 4 is a bottom view of the closure of FIG. 1;

FIG. 5 is a top view of the closure of FIG. 1;

FIG. 6 is a schematic view showing various components of the closure ofFIG. 1;

FIG. 7 is a top, perspective view of an expansion component of theclosure of FIG. 1;

FIG. 8 is a bottom, perspective view of the expansion component of theclosure of FIG. 1;

FIG. 9 shows a ruggedized adapter and ruggedized connector suitable foruse with the closure of FIG. 1;

FIG. 10 shows the closure of FIG. 1 equipped with components (e.g.,optical power splitters, optical wavelength dividing components, etc.)for increasing the service capacity of the closure;

FIG. 11 is a plan view of a first component tray adapted for use withthe closure of FIG. 1;

FIG. 12 is a perspective view of the component tray of FIG. 11;

FIG. 13 is a cross-sectional view taken along section line 13-13 of FIG.11;

FIG. 14 is a cross-sectional view taken along section line 14-14 of FIG.11;

FIG. 15 is a plan view of the component tray of FIG. 11 with wavelengthsplitting components and splicing components secured thereto;

FIG. 16 is a perspective view of the component tray of FIG. 11 withwavelength splitting components and splicing components secured thereto;

FIG. 17 is a cross-sectional view taken along section line 17-17 of FIG.15;

FIG. 18 is a cross-sectional view taken along section line 18-18 of FIG.15;

FIG. 19 shows an inner passage of a radial extension of the closure ofFIG. 1, component trays are shown mounted within the inner passage;

FIG. 20 is a diagrammatic cross-sectional view showing the componenttray of FIG. 11 mounted in one of the radial extensions of the closureof FIG. 1, a first fiber routing path of the component tray is alsoshown;

FIG. 21 is the same view as FIG. 20 showing a second fiber routing path;

FIG. 22 is the same view as FIG. 20 showing a third fiber routing path;

FIG. 23 is the same view as FIG. 20 showing a fourth fiber routing path;FIG. 11 is a plan view of a first component tray adapted for use withthe closure of FIG. 1;

FIG. 24 is a plan view of a second component tray adapted for use withthe closure of FIG. 1;

FIG. 25 is a perspective view of the component tray of FIG. 24;

FIG. 26 is a cross-sectional view taken along section line 26-26 of FIG.24;

FIG. 27 is a cross-sectional view taken along section line 27-27 of FIG.24;

FIG. 28 is a plan view of the component tray of FIG. 24 with powersplitting components and splicing components secured thereto;

FIG. 29 is a perspective view of the component tray of FIG. 24 withpower splitting components and splicing components secured thereto;

FIG. 30 is a cross-sectional view taken along section line 30-30 of FIG.28; and

FIG. 31 is a cross-sectional view taken along section line 31-31 of FIG.28.

DETAILED DESCRIPTION

The present disclosure relates generally to closures adapted for use infiber optic communications networks. In certain embodiments, theclosures can be environmentally sealed and can be re-enterable. Incertain embodiments, the closures can be configured to provide opticalconnections in the form of optical splices or connectorized connections.

FIGS. 1-6 show a closure 20 in accordance with the principles of thepresent disclosure. The closure 20 defines a central longitudinal axis22 that extends along a length of the closure 20 from a bottom end 24and a top end 26. A base 28 defines the bottom end 24 of the closure 20while a dome 30 defines the top end 26 of the closure 20. The base 28defines a plurality of cable through-ports 32 for allowing cables (e.g.,trunk cables, drop cables or other cables) to enter the closure 20. Thebase 28 supports a frame 33 (see FIG. 2) to which a stack of pivotalsplice trays 35 are mounted. An expansion component 34 mounts betweenthe dome 30 and the base 28. The frame 33 extends through the expansioncomponent 34. The expansion component 34 includes expansion housings 36having interior regions adapted to be in communication with the interiorof the dome 30 and the interior of the base 28. The expansion housings36 are positioned on opposite sides of the axis 22 and have dimensions d(see FIG. 5) that project radially outwardly from the axis 22. As shownat FIGS. 4 and 5, expansion housings 36 are positionedradially/laterally outside a main cylindrical outer boundary 37 definedby the dome 30. A plurality of ruggedized fiber optic adapters 38 aremounted to the expansion housings 36. The ruggedized fiber opticadapters 38 include connector ports 84 (see FIG. 9) for receivingruggedized fiber optic connectors. In the embodiment depicted in FIG. 1,the connector ports 84 and the cable through-ports 32 face in a downwarddirection and have axes that are generally parallel with respect to theaxis 22. In FIGS. 1-5, dust caps 93 are shown mounted in the ports 84.

The dome 30 of the closure 20 includes a closed top end 42 and an openbottom end 44. The closed top end 42 defines the top end 26 of theclosure 20 and the open bottom end 44 is configured for a connection tothe expansion component 34. In one embodiment, a circumferential flange46 is provided at the open bottom end 44 for facilitating coupling thedome 30 to the expansion component 34 with a clamp.

The base 28 of the closure 20 includes a top end 48 positioned oppositefrom a bottom end 50. The bottom end 50 defines the bottom end 24 of theclosure 20, and the top end 48 is adapted to be connected to theexpansion component 34. In the depicted embodiment, the top end 48includes a circumferential flange 52 for facilitating coupling the base28 to the expansion component 34 with a clamp. A cable sealingarrangement is provided within the base 28. The sealing arrangement canbe actuated by an actuator 54 which causes sealing material within thebase 28 to be compressed in a direction along the axis 22. When thesealing material is axially compressed, the material deforms radiallyinwardly about the cables within the through-ports 32 thereby formingcircumferential seals around cables.

Referring to FIGS. 7 and 8, the expansion component 34 of the closure 20includes a central collar 55 that mounts between the open bottom end 44of the dome 30 and the top end 48 of the base 28. The collar 55 can alsobe referred to as a spacer or a sleeve. An upper end of the collar 55includes a circumferential flange 56 adapted to be clamped to thecircumferential flange 46 at the bottom of the dome 30. A lower end ofthe collar 55 includes a circumferential flange 58 adapted to be clampedto the circumferential flange 52 at the top end 48 of the base 28. FIG.6 shows a first channel clamp 61 being used to clamp the flanges 46, 56together and a second the channel clamp 63 being used to clamp theflanges 52, 58 together. When clamped in place, the collar 55 isgenerally coaxially aligned with the dome 30 and the base 28.

The central collar 55 includes an axial dimension Al that is selected toinsure that the collar 55 does not interfere with the ability of thesplice trays 35 to pivot relative to the frame 33. As shown at FIG. 3,the top end of the collar 55 coincides with a location where the splicetrays 35 are pivoted to an open position. In the depicted embodiment,the splice trays 35 are pivoted about 90 degrees relative to the frame33 when the splice trays are 35 in the open position.

Referring still to FIGS. 7 and 8, the expansion housings 36 of theexpansion component 34 include main housings 36 a and radial extensions36 b that connect the main housings 36 a to the collar 55. The mainhousings 36 a have enlarged internal volumes as compared to the radialextensions 36 b. The radial extensions 36 b define radial fiber passages71 that provide communication between interior regions of the mainhousings 36 a and an exterior region of the collar 55. The interiorregion of the collar 55 is also in communication with an interior regionof the dome 30 and an interior region of the base 28. Reinforcing wallportions 222 (e.g., webs) can extend across heights of the fiberpassages 71. The wall portions 222 are located at the ends of thepassages 74 that are positioned adjacent the collar 55. The wallportions 222 have curvatures that extend about the central axis 22 andalso have heights that extend along the axial dimension A1. The wallportions 222 provide crush resistance in the axial orientation. Theradial extensions 36 b can also include tray guide rails 223 provided atside walls 225 of the radial extensions 36 b.

The main housings 36 a of the expansion component 34 are shaped to curvegenerally about the axis 22 of the closure 20. Bottom sides of the mainhousings 36 a are defined by adapter mounting walls 72 having outersurfaces 74 that face in a downward direction. Adapter mounting openings76 extend through the adapter mounting walls 72. The ruggedized fiberoptic adapters 38 are mounted within the adapter mounting openings 76.The adapter mounting openings 76 of each of the main housings 36 a arepositioned along a curve located radially outside the main cylindricalboundary 37 defined by the dome 30. The fiber optic adapters 38 areaxially offset (e.g., upwardly offset) from the through-ports 32 of thebase 28 and are also radially outwardly offset from the through-ports 32of the base 28.

FIG. 9 shows one of the ruggedized fiber optic adapters 38 and acorresponding ruggedized fiber optic connector 80 adapted to be receivedwithin the fiber optic adapter 38. The fiber optic connector 80 is shownmounted at the end of a drop cable 81. The fiber optic adapter 38includes an inner port 82 adapted for receiving a connector such as anSC connector 83 (see FIG. 6), and an outer port 84 adapted for receivingone of the ruggedized fiber optic connectors 80. When the fiber opticconnector 80 and the fiber optic connector 83 are inserted within one ofthe fiber optic adapters 38, an optical connection is provided betweenthe connectors 80, 83. The fiber optic adapter 38 can include a latch 85for retaining the fiber optic connector 83 within the inner port 82.Internal threads 87 can be provided in the outer port 84. The threads 87cooperate with external threads 89 of a threaded nut 95 provided on theruggedized fiber optic connector 80 to retain the ruggedized fiber opticconnector 80 within the outer port 84. An alignment sleeve 91 isprovided within the fiber optic adapter 38 for aligning ferrules of theconnectors 80, 83.

When the fiber optic adapter 38 is mounted within one of the adaptermounting openings 76 of the expansion component 34, the adapter mountingwall 72 is captured between a flange 86 of the adapter 38 and aretention nut 88. A sealing member 97 in the form of an o-ring can beused to provide a seal between the housing of the fiber optic adapter 38and the outer surface 74 of the adapter mounting wall 72.

The main housings 36 a have axial dimensions A2 that are larger thancorresponding axial dimensions A3 of the radial extensions 36 b. Theaxial dimensions A2 are larger than the axial dimensions A3 at least inpart because of axial extension portions 99 that project downwardly fromthe radial extensions 36 b. The axial extension portions 99 function todownwardly offset the adapter mounting walls 72 from the radialextensions 36 b. The enlarged axial dimensions A2 provide more axialspace within the main housings 36 a (i.e., between the upper and lowerwalls of the main housings 36 a) for routing fibers. For example,sufficient space is provided for bending optical fibers corresponding tothe connectors 83 without violating minimum bend radius requirements forthe optical fibers. As shown at FIG. 6, the optical fibers coupled tothe connectors 83 are bent about 90 degrees as the optical fibers arerouted from the connectors 83 within the fiber optic adapters 38 to thefiber passages 71 of the radial extensions 36 b. Furthermore, as shownat FIG. 6, a gap/open space 220 defined radially between the axialextension portions 99 and the central collar 55 provides clearance formounting and accessing the clamp 63.

The closure 20 is adapted to accommodate both splice connections andconnectorized connections (e.g., connections using ruggedizedconnectors). For example, FIG. 6 shows a trunk cable 100 routed throughthe interior of the closure 20. The trunk cable 100 extends through thethrough-ports 32 provided at the base 28. As shown at FIG. 6, one ormore of the fibers of the trunk cable 100 can be spliced tocorresponding fibers of a drop cable 102 that is also routed through acable through-port 32 of the base 28. In this way, the closure 20accommodates a spliced connection with a drop cable. To accommodate apre-connectorized drop cable, the pre-connectorized drop cable can beplugged into the outer port 84 of one of the fiber optic adapters 38.When the connector of the pre-connectorized drop cable is insertedwithin the outer port 84, it optically connects to a correspondingconnector 83 that has been pre-mounted within the inner port of theadapter 38. The connector 83 can be mounted directly to one of theoptical fibers of the trunk cable 100. For example, the connector 83 canbe field terminated on the fiber. Alternatively, the connector 83 can bemounted at the end of a pigtail fiber that is spliced to a correspondingone of the fibers of the trunk cable 100 at the splice location.

The main housings 36 a can include outer end covers 73 that areremovable from main bodies of the main housings 36 a. By removing theend covers 73, interior regions of the main housings 36 a can be easilyaccessed for loading trays into the radial extensions 36 b, for routingconnectors 83 to the inner ports of the adapters 38, or for serviceoperations or maintenance activities.

The configuration of the expansion component 34 is ideally suited foruse in retrofitting/upgrading existing splice closures that are alreadyin operation in the field. To upgrade such a closure, the dome 30 of theclosure can be removed and the expansion component 34 can be mounted tothe base of the closure. The connectors 83 mounted within the innerports 82 of the fiber optic adapters 38 can then be optically connectedto optical fibers of one or more trunk/feeder cables routed into and/orthrough the closure. For example, the connectors 83 can be fieldterminated at ends of selected fibers of the trunk cables.Alternatively, the connectors 83 can be mounted at the end of pigtailswhich are spliced to fibers of the trunk cables. Once the connectors 83mounted within the inner ports of the adapters 38 are connected toselected fibers of the trunk cable, the dome 30 of the splice closurecan then be clamped to the top end of the collar 55 and the upgrade iscomplete.

Further details relating to the fiber optic adapter 38 and theruggedized fiber optic connector 80 can be found in U.S. Pat. No.7,744,288, which is hereby incorporated by reference in its entirety. Inother embodiments, other types or styles of fiber opticadapters/connectors can be used at the expansion component 34. Forexample, other fiber optic adapters and fiber optic connectors that canbe used at the expansion component 34 are disclosed at U.S. Pat. Nos.6,579,014; 6,899,467; and 7,090,406. The above connectors systems allrelate to the connection of single fibers. In still further embodiments,multi-fiber connection systems can be used at the expansion component.Example multi-fiber connectors and adapters are disclosed at U.S. Pat.Nos. 7,785,016 and 7,264,402; which are hereby incorporated by referencein their entireties.

For the purpose of providing a closure design suitable for retrofittingexisting splice closures, it is desirable for the expansion component 34to be a separate piece from the dome 30 and the base 28. However, inalternative embodiments, the expansion component 34 can be integrallyformed with either the dome 30 or the base 28.

In certain embodiments, the expansion component 34 can includeadditional structures for increasing the service capacity of theclosure. Example structures can include passive components such asoptical power splitters and structures for providing optical wavelengthsplitter/dividing/filtering. Optical power splitters are capable ofsplitting an entire optical signal carried by one optical fiber to twoor more optical fibers (e.g., 1 by 2 splitters; 1 by 4 splitters; 1 by 8splitters, 1 by 16 splitters; 1 by 32 splitters, etc.), and are alsocapable of combining optical signals from multiple fibers back to oneoptical fiber. Wavelength splitting/dividing structures (e.g., coarsewavelength dividing multiplexers and de-multiplexers, dense wavelengthdividing multiplexers and de-multiplexers, array waveguide gradingstructures, etc.) are capable dividing an optical signal carried by oneoptical fiber into separate wavelength ranges with each range then beingdirected to and carried by a separate optical fiber, and are alsocapable of combining separate wavelength ranges carried by separateoptical fibers back to one optical fiber.

FIG. 10 shows the expansion component 34 equipped with service capacityincreasing components 200 a, 200 b of the type described in the previousparagraph (e.g., optical power splitters, optical wavelength splitters,etc.). The components 200 a, 200 b are shown mounted in the passages 71defined by the radial extensions 36 b. An input fiber 202 to thecomponent 200 a is shown spliced to a corresponding optical fiber of thetrunk cable 100 and output fibers 204 of the component 200 a are coupledto the fiber optic connectors 83 inserted within the inner ports of thefiber optic adapters 38. An input fiber 206 of the component 200 b isprovided by one of the optical fibers of the trunk cable 100. The inputfiber 206 has a connectorized end 208 that connects to the component 200b in a plug-and-play type configuration. Further details about exampleplug-and-play type connections for optical splitters are disclosed atU.S. Pat. Nos. 7,376,322; 7,400,813; 7,376,323; and 7,346,254; which arehereby incorporated by reference in their entireties. Output fibers 210of the component 200 b are coupled to the fiber optic connectors 83inserted within the inner ports of the fiber optic adapters 38.

FIGS. 11-18 show a component tray 300 a (i.e., cassette) adapted to bemounted within the passage 71 of one of the radial extensions 36 b. Thecomponent tray 300 a is configured to securely retain optical componentssuch as splice sleeves 302 and wavelength splitting components 304. Thesplice sleeves are structures for reinforcing a slice (e.g., a fusionsplice) between two optical fibers. A splice sleeve typically includesan inner adhesive layer surrounded by a heat shrink layer. Splicesleeves also typically include axial reinforcing members attached to theheat shrink layer. As shown at FIGS. 15-18, the splice sleeves 302 andthe components 304 are generally cylindrical. The components 304 havelarger diameters as compared to the splice sleeves 302.

The first component tray 300 a is sized and shaped to fit within one ofthe radial extensions 36 b without projecting substantially into thecollar 55 or the main housings 36 a. As shown at FIG. 19, the componenttray 300 a is mounted at a lower mounting location of one of the radialextensions 36 b, and another component tray 300 b (see FIGS. 24-31) ismounted at an upper mounting location of the radial extension 36 b. Incertain embodiments, each of the radial extensions 36 b can be loadedwith component trays 300 a, 300 b so as to maximize the circuit densityprovided by the expansion component 34.

Referring to FIG. 11, the component tray 300 a has a generallykidney-shaped perimeter when viewed in plan view. The perimeter isdefined in part by a concave side 306 of the tray 300 a and an oppositeconvex outer side 308 of the tray 300 a. The perimeter is also definedby opposite ends 310, 312 of the tray 300 a that extend between theconcave and convex sides 306, 308. The ends 310, 312 are substantiallyparallel to one another. The tray 300 a includes a base 314 and aperimeter wall arrangement 316 that projects upwardly from the base 314.The perimeter wall arrangement 316 extends around the perimeter of thetray 300 a and cooperates with the base 314 to define a protected fibermanagement volume/space 318 above the base 314. Fiber retention tabs 320project inwardly from the perimeter wall arrangement 316. The tabs 320are spaced above the base 314 and overhang the fiber management space318. The tabs 320 function to retain optical fibers routed on the tray300 a within the fiber management space 318. Some of the tabs 320include receptacles 322 for receiving fasteners (e.g., snap-fitfasteners) used to secure a cover over the top of the space 318.

Referring still to FIG. 11, the tray 300 a is symmetric about a centralaxis 324. The tray 300 a includes two fiber entrance/exit locations 326,328 positioned at the concave side 306 of the tray and two fiberentrance/exit locations 330, 332 positioned at the convex side 308 ofthe tray. The locations 326, 330 are at one end 310 of the tray and thelocations 328, 332 are located at the other end 312 of the tray. Thelocations 326, 328 define fiber routing paths P1, P2 that aresubstantially parallel to the central axis 324, while the locations 330,332 define fiber routing paths P3, P4 that converge toward and intersectat the central axis 324. Tie down structures 333 are provided at each ofthe exit/entrance locations for allowing tubing protecting the opticalfibers to be tied down (e.g., with cable ties) to the tray.

The tray 300 a includes structures for facilitating securing the traywithin the bottom mounting location of one of the radial extensions 36b. For example, the tray 300 a includes flanges 336 that projectoutwardly from the opposite ends 310, 312 at locations adjacent the topof the tray 300 a. When the tray 300 a is mounted within one of theradial extensions 36 b, the flanges 336 slide beneath the side rails 223of the extension 36 b. The tray 300 a also includes resilient retentionlatches 338 positioned at the concave side 306 of the tray 300 a. Thelatches 338 are positioned between the central axis 324 and the fiberentrance/exit locations 326, 328 and are adapted to latch (e.g., by asnap fit connection) over the edges the walls 222 of the radialextension 36 b when the tray 300 a is fully inserted therein. Thelatches 338 include a flexible cantilever portion 340, a cam portion 342and a catch 344. The cantilever portion 340 is substantially parallel tothe central axis 324 and the cam portions 342 define cam surfacesaligned along planes P5, P6 that are angled relative to the central axis324. The planes P5, P6 converge as the planes extend toward the concaveside 306 of the tray 300 a. The concave shape of the tray provides arecess 346 between the latches 338. The recess 346 provides clearancefor the walls 222 when the tray 300 a is latched within one of theradial extensions 36 b.

To load the tray 300 a into the radial extension 36 b, the cover 73 isremoved from the corresponding main housing 36 a. The tray 300 a is theninserted though the open side of the main housing 36 a in a radialdirection directed toward the central axis 22 of the expansion component34. The insertion direction is parallel to the central axis 324 of thetray 300 a. As the tray 300 a is inserted into the radial extension 36b, the flanges 336 ride beneath the rails 223 in close proximity to theside walls 225. Continued insertion of the tray 300 a toward the axis 22brings the cam surfaces of the cam portions 342 into contact with thewalls 222. Contact between the cam portions 342 and the walls 222 causesthe cantilever portions 340 to flex such that the latches 338 flex awayfrom each other (i.e., apart) to provide clearance for the walls 222.Once the catches 344 move past the edges of the walls 222, the latches338 snap (i.e., elastically return) to a retention position (see FIG.20) where the catches engage inner sides of the walls 222 so as toretain the tray 300 a within the extension 36 b.

Referring to FIGS. 20-23, component mounting locations 350 a, 350 b arepositioned at a central region of the tray 300 a and excess fiberstorage locations 352 are positioned adjacent the ends of the tray 300a. The excess fiber storage locations 352 are adapted for storingoptical fiber 354 in a looped/coiled configuration. The locations 352are defined in part by inner surfaces of the perimeter wall arrangement316 and in part by curved cable management walls 353 positioned withinthe fiber management space 318. The coils can be positioned inside oroutside the walls 353 based on user preference. FIGS. 20-23 show variousoptical fiber routing schemes/paths in which optical fibers are routedfrom one of the fiber entrance/exit locations 326, 328 through one ofthe component mounting locations 350 a, 350 b to one of the fiberentrance/exit locations 330, 332. For ease of depiction, splits are notshown at the wavelength splitting components 304. However, it will beappreciated that multiple output fibers can be provided from eachcomponent 304 for each input fiber as shown at FIG. 10. All of thedepicted routing schemes involve routing the fibers 354 around theinside of the perimeter of the tray 300 a. Only FIG. 20 shows excessfiber being coiled at the locations 352. However, it will be appreciatedthat fiber can be similarly coiled in any of the routing schemes toaccommodate excess fiber length. The angling of the fiber entrance/exitlocations 330, 332 along orientations P3 and P4 facilitates routingfibers to adapters 38 located on opposite sides of the central axis 324from the respective locations 330, 332 without violating minimum bendradius requirements of the optical fibers

The component mounting locations 350 a, 350 b have a compactconfiguration adapted for securely attaching optical components to thetray 300 a. The component mounting location 350 a is adapted formounting wavelength splitting components 304 to the tray 300 a and thecomponent mounting location 350 b is adapted for mounting splice sleeves302 to the tray 300 a. The retention structures provided at thelocations 350 a, 350 b are the same, except that the components providedat location 350 a are larger than those provided at location 350 b.

The retention structures provided at the component mounting locations350 a, 350 b define a plurality of elongated pockets 392 (i.e.,cavities, receptacles, component receiving locations, receptacles)having lengths aligned substantially perpendicular relative to thecentral axis 324. The pockets 392 of each location 350 a, 350 b arearranged in a row of pockets with the lengths of the pockets beingsubstantially parallel to one another. Each of the pockets 392 isdefined between two resilient retention members 394 that aresubstantially parallel to one another and that extend at least amajority of the length of the pocket 392. The resilient retentionmembers 394 have cantilevered configurations with base ends 396integrally formed (e.g., molded as one seamless piece) with the base314. The resilient retention members have elastic/spring-likecharacteristics when bent about their base ends 396 in an orientationtransverse to their lengths (e.g., orientation 395). The retentionmembers 394 include concave sides 397 that face at least partiallytoward the base 314 (e.g., downwardly) and that overhang the pockets392. The retention members 394 also include convex sides 398 that faceaway from the base 314 (e.g., upwardly). The concave sides 397 at leastpartially oppose the convex sides 398 of adjacent retention members 394such that the sides 397, 398 cooperate to define lateral boundaries ofthe pockets 392. Through-slots 399 are defined through the base 314 atlocations directly beneath the overhanging portions of the concave sides397 of the retention members 394. The base 314 defines pocket beds 400between the slots 399 and the convex sides 398 of the retention members394. The pocket beds 400 include component support surfaces that arerecessed relative to a main level 402 of the base 314. End shoulders 403are defined at the interface between the component support surface andthe main level 402.

To load an optical component into one of the component mountinglocations 350 a, 350 b, the component is pressed between the concaveside 397 and the convex side 398 of two adjacent retention members 394.As the component is inserted between the sides 397, 398, the retentionmembers 394 elastically flex/deflect apart providing clearance for thecomponent to enter the pocket. After the component passes a point ofmaximum deflection of the retention members 394, the component is forcedtoward the pocket bed 400 by the retention members 394 as the retentionmembers 394 are elastically biased toward a retaining configuration (seeFIG. 17) where the component is captured within the pocket. In certainembodiments, the retention position is a neutral position where theretention members 394 are not deflected. In other embodiments, theretention members 394 can be deflected when in the retention position toapply an elastic retention force to the component. When the component isseated in the pocket, the shoulders 403 limit axial movement of thecomponent within the pocket (see FIG. 18).

FIGS. 24-31 show the tray 300 b that is adapted to be mounted at theupper mounting positions of the radial extensions 36 b. The tray 300 bhas the same basic configuration as the tray 300 a except flanges 336are located at a bottom side of the tray 300 b such that the flanges canride on top sides of the rails 223 when the tray is inserted into theupper position of one of the radial extensions 36 b. Additionally, thetray 300 b includes a component mounting location 350 c adapted forsecuring rectangular components such as optical power splitters 303 tothe tray 300 b.

The retention structures provided at the component mounting location 350c define a plurality of elongated pockets having lengths alignedsubstantially perpendicular relative to the central axis 324. Thepockets are arranged in a row of pockets with the lengths of the pocketsbeing substantially parallel to one another. Each of the pockets isdefined between two pairs of resilient retention members 370. Theresilient retention members 370 have cantilevered configurations withbase ends integrally formed (e.g., molded as one seamless piece) withthe base 314. The resilient retention members have elastic/spring-likecharacteristics when bent about their base ends in an orientationtransverse to their lengths. As shown at FIG. 26, the retention members370 include retention heads 372 each having two cam surfaces 374 thatmeet at an apex 376. The cam surfaces 374 face upwardly and outwardlyand converge as they extend upwardly. Each retention head also includesa retention surface 378 positioned beneath each cam surface 374. Theretention surfaces 378 face toward the base 314 (e.g., downwardly) andoverhang pockets separated by the main cantilever body of each retentionmember 370. Through-slots 380 are defined through the base 314 atlocations directly beneath the retention surfaces 378. The base 314defines pocket beds 382 between the slots 380. The pocket beds 382include component support surfaces (see FIG. 27) that are recessedrelative to the main level 402 of the base 314. End shoulders 385 aredefined at the interface between the component support surface and themain level 364.

To load an optical component into the component mounting locations 350c, the component is pressed between two of the retention members 370. Asthe component is pushed downwardly, the component engages the camsurfaces 374 positioned at opposite sides of the pocket causing theretention members 370 to deflect apart providing clearance for thecomponent to enter the pocket. After the component passes a point ofmaximum deflection of the retention members 370, the component seats onthe pocket bed 382 and the retention members 370 elastically move backtoward a retaining configuration (see FIG. 30) where the component iscaptured within the pocket beneath the retention surfaces 378. When thecomponent is seated in the pocket, the shoulders 385 limit axialmovement of the component within the pocket (see FIG. 31).

While various integral component retention structures are disclosed, itwill be appreciated that in other embodiments non-integral retentionstructures can be used as well.

Various aspects of the disclosure are shown with respect to a dome-stylesplice closure. In alternative embodiments, it will be appreciated thataspects of the present disclosure can be used with other types ofclosures such as in-line closures, or other types of closures.

The various embodiments disclosed herein have been described usingdirectional terms (e.g., upper, lower, top, bottom, etc.) merely forease of describing the relative positioning of the various parts. Inpractice, it will be appreciated that the embodiments disclosed hereincan be used in any orientation. For example, for aerial applications,the enclosures described herein might typically be oriented horizontally(i.e., with the central axes extending horizontally). In contrast, forpole mount applications, the enclosures described herein might typicallybe oriented vertically (i.e., with the central axes extendingvertically).

As used herein, the phrase “generally parallel” means parallel or almostparallel. Also, the phrase “generally perpendicular” means perpendicularor almost perpendicular.

From the foregoing detailed description, it will be evident thatmodifications and variations can be made in the devices of thedisclosure without departing from the spirit or scope of the invention.

1. A fiber optic communications arrangement comprising: (a) a closurewith an interior volume; the closure including at least one cablethrough-port in communication with the interior volume; and (b) anexpansion component attached to an exterior portion of the closure andhaving an interior region in communication with the closure interiorvolume, the expansion component including a plurality of ruggedizedfiber optic adapters mounted thereto; each of the ruggedized fiber opticadapters including at least one connector port for receiving ruggedizedfiber optic connectors.
 2. The arrangement of claim 1 wherein theexpansion component includes an optical power splitter.
 3. Thearrangement of claim 1 wherein the expansion component includes anoptical wavelength splitter.
 4. The arrangement of claim 1 wherein theexpansion component includes passive components.
 5. The arrangement ofclaim 1 wherein the closure includes one or more splice trays.
 6. Thearrangement of claim 1 wherein the closure has a plurality ofthrough-ports.
 7. The arrangement of claim 6 further including a cablesealing arrangement within the closure, the sealing arrangementincluding a sealing material.
 8. The arrangement of claim 7 furtherincluding an actuator configured and arranged to cause the sealingmaterial within the closure to be compressed and deform radiallyinwardly about fiber optic cables when laid within the through-ports,thereby forming circumferential seals around fiber optic cables.
 9. Thearrangement of claim 1 wherein the expansion component includes aplurality of expansion housings, with the ruggedized fiber opticadapters mounted to the expansion housings.
 10. The arrangement of claim9 wherein: (a) the closure defines a central longitudinal axis extendingalong a length of the closure from a bottom end and a top end; thebottom end being defined by a base, and the top end being defined by adome; and (b) the expansion housings are positioned on opposite sides ofthe axis.